A work vehicle having a first vehicle portion pivotally connected to a second vehicle portion of articulating motion often experience serious pitching or vertical movement of one of the vehicle portions relative to the other. An example vehicle would be a tractor-scraper wherein heavy dirt loads are carried by a bowl of the first vehicle means. As the weight of the loads increases, it has been found that the magnitude of the pitch or vertical movement of the second vehicle portion increases. This causes an operator riding on the second vehicle portion to be undesirably bounced around during operation of the vehicle. These undesirable pitching motions result from the geometry of the vehicle and the position of the bowl.
Heretofore, apparatus has been constructed to restrict this undesirable movement. Although such apparatus suppress this undesirable bounce, it is desirable to provide apparatus which is of more simple construction, is easier to maintain and function to more effectively suppress the undesirable bounce.
The present invention is directed to overcome one or more of the problems as set forth above.
According to the present invention, a work vehicle has first and second vehicle portions each having an axle assembly and being horizontally pivotally connected one to the other by hitch means at a location substantially directly over the axle of the second vehicle portion. A second means is provided for vertically pivotally connecting the first and second vehicle portions together. The frame member has first and second end portions and a middle portion connectable to the second axle assembly with said first end portion being of a configuration sufficient for overlaying the second axle assembly in the connected position. Means is positioned between and is connected to the second axle assembly and the first end portion of the frame member for controllably biasing the first end portion of the frame member against movement toward and from the underlying second axle assembly.